add optimize to main imports
add optimize to main imports

mikegraham/dask,simudream/dask,vikhyat/dask,jayhetee/dask,marianotepper/dask,gameduell/dask,dask/dask,dask/dask,mraspaud/dask,hainm/dask,mraspaud/dask,clarkfitzg/dask,freeman-lab/dask,marianotepper/dask,ssanderson/dask,jcrist/dask,vikhyat/dask,cpcloud/dask,esc/dask,pombredanne/dask,wiso/dask,ContinuumIO/dask,jakirkham/dask,jayhetee/dask,pombredanne/dask,ContinuumIO/dask,clarkfitzg/dask,PhE/dask,chrisbarber/dask,freeman-lab/dask,simudream/dask,blaze/dask,esc/dask,minrk/dask,minrk/dask,blaze/dask,jakirkham/dask,cowlicks/dask,mrocklin/dask,hainm/dask,wiso/dask,ssanderson/dask,PhE/dask,jcrist/dask,mrocklin/dask